The current study aimed to identify the level of cognitive flexibility and the big five personality factors of Sultan Qaboos University students and to identify the gender differences in the three independent variables (cognitive flexibility, the big five personality factors), and the possibility of predicting academic achievement through cognitive flexibility and the big five personality factors. The study sample consisted of 250 male and female students. The study tools were represented in the cognitive flexibility scale (Dennis & Vander wall, 2009), which the researcher translated, and the scale of the Arabic list of the, big five major factors of personality by Ahmed Abdel Khaleq (2020). The arithmetic mean of the openness dimension was high, while the arithmetic mean of the dimension of extraversion, acceptance and mastery was medium, and in contrast, the arithmetic mean of the neuroticism dimension is at a low level, and there are statistically significant differences between males and females in the cognitive flexibility axis in the alternatives dimension in favor of females, as for the axis of The big Five Personality Factors. The results indicate that there are statistically significant differences between males and females in the dimension of openness in favor of females, while there are no statistically significant differences between males and females in the dimensions of extraversion, neuroticism, acceptance and mastery, and the results indicate the possibility of predicting academic achievement through the alternatives and mastery variable.